In order to decrease costs and increase efficiency, telephone companies are automating directory assistance systems. An early step toward automation of directory assistance was the use of store and forward technology to assist live operators. A caller was asked for a locality by a pre-recorded prompt. The store and forward system stored a compressed version of the caller's response to the prompt, and brought a live operator onto the line. The operator heard the compressed version of the response and then completed the remaining dialogue with the caller to provide a unique telephone number.
With the advent of speech recognition, companies have begun adding speech recognition capabilities to directory assistance systems. Automated speech recognition recognizes a locality from the caller's response to a prompt for locality. In a typical system, if the speech recognition is successful, the system prompts the caller for the listing name, puts an operator on the line, populates the operator's workstation display with the recognized locality, and plays a recorded compressed version of the caller's response to the listing question. The operator then conducts the remaining dialogue, searches for the listing, and provides the unique telephone number to the caller. But directory assistance is not totally automated and operator involvement is still required in providing the callers telephone numbers.